Up-regulating pyocyanin production by amino acid addition for early electrochemical identification of Pseudomonas aeruginosa

This work focuses on developing a faster method for electrochemically detecting a Pseudomonas aeruginosa infection through the addition of amino acids to cell culture samples. We performed square-wave voltammetry measurements of pyocyanin produced by P. aeruginosa using commercially available carbon-based electrodes connected to a Ag/AgCl reference. The electrochemical response resulting from the production of pyocyanin by bacteria was measured in the presence of various amino acids while varying three different culturing parameters: liquid media type (trypticase soy broth vs. M63 minimal media); concentration of amino acids in the solution; and initial concentration of the P. aeruginosa in the solution. Our results demonstrate a faster and stronger electrochemical response in media containing tyrosine and valine at elevated concentrations, lending promise to using amino acids as up-regulatory molecules for faster bacterial detection.